Rationale and design of the Pemafibrate to Reduce Cardiovascular Outcomes by Reducing Triglycerides in Patients with Diabetes (PROMINENT) study

Impact of peroxisome proliferator-activated receptor-α on diabetic cardiomyopathy

The prevalence of cardiomyopathy is higher in diabetic patients than those without diabetes. Diabetic cardiomyopathy (DCM) is defined as a clinical condition of abnormal myocardial structure and performance in diabetic patients without other cardiac risk factors, such as coronary artery disease, hypertension, and significant valvular disease. Multiple molecular events contribute to the development of DCM, which include the alterations in energy metabolism (fatty acid, glucose, ketone and branched chain amino acids) and the abnormalities of subcellular components in the heart, such as impaired insulin signaling, increased oxidative stress, calcium mishandling and inflammation. There are no specific drugs in treating DCM despite of decades of basic and clinical investigations. This is, in part, due to the lack of our understanding as to how heart failure initiates and develops, especially in diabetic patients without an underlying ischemic cause. Some of the traditional anti-diabetic or lipid-lowering agents aimed at shifting the balance of cardiac metabolism from utilizing fat to glucose have been shown inadequately targeting multiple aspects of the conditions. Peroxisome proliferator-activated receptor α (PPARα), a transcription factor, plays an important role in mediating DCM-related molecular events. Pharmacological targeting of PPARα activation has been demonstrated to be one of the important strategies for patients with diabetes, metabolic syndrome, and atherosclerotic cardiovascular diseases. The aim of this review is to provide a contemporary view of PPARα in association with the underlying pathophysiological changes in DCM. We discuss the PPARα-related drugs in clinical applications and facts related to the drugs that may be considered as risky (such as fenofibrate, bezafibrate, clofibrate) or safe (pemafibrate, metformin and glucagon-like peptide 1-receptor agonists) or having the potential (sodium-glucose co-transporter 2 inhibitor) in treating DCM.

Selective Peroxisome Proliferator-Activated Receptor Alpha Modulators (SPPARMα) in the Metabolic Syndrome: Is Pemafibrate Light at the End of the Tunnel?

Purpose of Review

Adoption of poor lifestyles (inactivity and energy-dense diets) has driven the worldwide increase in the metabolic syndrome, type 2 diabetes mellitus and non-alcoholic steatohepatitis (NASH). Of the defining features of the metabolic syndrome, an atherogenic dyslipidaemia characterised by elevated triglycerides (TG) and low plasma concentration of high-density lipoprotein cholesterol is a major driver of risk for atherosclerotic cardiovascular disease. Beyond lifestyle intervention and statins, targeting the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARα) is a therapeutic option. However, current PPARα agonists (fibrates) have limitations, including safety issues and the lack of definitive evidence for cardiovascular benefit. Modulating the ligand structure to enhance binding at the PPARα receptor, with the aim of maximising beneficial effects and minimising adverse effects, underlies the SPPARMα concept.

Recent Findings

This review discusses the history of SPPARM development, latterly focusing on evidence for the first licensed SPPARMα, pemafibrate. Evidence from animal models of hypertriglyceridaemia or NASH, as well as clinical trials in patients with atherogenic dyslipidaemia, are overviewed.

Summary

The available data set the scene for therapeutic application of SPPARMα in the metabolic syndrome, and possibly, NASH. The outstanding question, which has so far eluded fibrates in the setting of current evidence-based therapy including statins, is whether treatment with pemafibrate significantly reduces cardiovascular events in patients with atherogenic dyslipidaemia. The PROMINENT study in patients with type 2 diabetes mellitus and this dyslipidaemia is critical to evaluating this.

Positive Association between Triglyceride-Rich Lipoprotein Cholesterol and Diabetes Mellitus in Hypertensive Patients

BACKGROUND

The association between triglyceride-rich lipoprotein cholesterol (TRL-C) and diabetes mellitus (DM) remains unclear because of limited research and data. The aim of this study was to explore the independent association between TRL-C and DM in hypertensive patients and to examine whether a healthy lifestyle would have an impact on this relationship.

METHODS

In this study, data from 13,721 hypertensive patients who were not treated with lipid-lowering drugs were analyzed. TRL-C was calculated from total cholesterol (TC) minus [LDL cholesterol + HDL cholesterol]. DM was defined as fasting plasma glucose of ≥7.0 mmol/L and/or self-reported history of hypoglycemic drug use.

RESULTS

After adjusting for potential confounding factors, the TRL-C was significantly positively associated with elevated DM (odds ratio (OR): 1.73 and 95% confidence interval (CI): 1.54-1.94). In subgroup analysis, a healthy lifestyle (HL) failed to modify the positive association between TRL-C and DM (HL: OR 1.93, 95%CI 1.58-2.36; non-HL: OR 1.72, 95%CI 1.50-1.98; P for interaction = 0.38).

CONCLUSION

The results showed a positive association between TRL-C and DM in hypertensive patients. A healthy lifestyle failed to diminish the relationship between TRL-C and DM. The novel findings indicate that TRL-C might be a reliable marker of DM and may provide a new strategy for the prevention and treatment of DM.

Metabolic Variation Dictates Cardiac Pathogenesis in Patients With Tetralogy of Fallot

BACKGROUND

Herein, we aimed to analyze cardiac metabolic reprogramming in patients with tetralogy of Fallot (ToF).

METHODS

Cardiac metabolic reprogramming was analyzed through comprehensive bioinformatics analysis, which included gene set enrichment, gene set variation, and consensus clustering analyses, so as to assess changes in metabolic pathways. In addition, full-spectrum metabolomics analysis was performed using right atrial biopsy samples obtained from patients with ToF and atrial septal defect (ASD) before cardiopulmonary bypass; ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to construct a metabolic map of cardiac metabolic reprogramming in cyanotic congenital heart disease.

RESULTS

The metabolic maps of carbohydrate metabolic process and heme metabolism were significantly activated, while bile acid metabolism, lipid droplet, and lipid binding were primarily restrained in ToF samples as compared with that in ASD samples. The reprogramming of butanoate metabolism was identified basing on the UPLC-MS/MS detection and analysis in myocardial hypoxia damage in cyanotic heart disease. Finally, the butanoate metabolism-related hub regulators ALDH5A1 and EHHADH were identified and they were significantly downregulated in ToF samples.

CONCLUSIONS

The metabolic network of butanoate metabolism involved ALDH5A1 and EHHADH, which could contribute to myocardial tissue damage in cyanotic congenital heart of ToF. Our results provide further insights into the mechanisms underlying metabolic reprogramming in cyanotic congenital heart disease and could lead to the identification of potential therapeutic targets.

Triglyceride-Rich Lipoprotein Cholesterol, Small Dense LDL Cholesterol, and Incident Cardiovascular Disease

BACKGROUND

Elevated triglyceride-rich lipoprotein (TRL) and small-dense low-density lipoprotein (sdLDL) particles are hallmarks of atherogenic dyslipidemia, and their cholesterol content is hypothesized to drive atherosclerotic risk. Prospective epidemiological data pertaining to cholesterol content of TRLs and sdLDL in primary prevention populations are mostly limited to coronary heart disease.

OBJECTIVES

The purpose of this study was to prospectively evaluate whether triglyceride-rich lipoprotein cholesterol (TRL-C) and small-dense low-density lipoprotein cholesterol (sdLDL-C) concentrations associate with composite and individual incident cardiovascular disease (CVD) outcomes including myocardial infarction (MI), ischemic stroke (IS), and peripheral artery disease (PAD).

METHODS

In a prospective case-cohort study within the Women's Health Study, TRL-C and sdLDL-C (mg/dl) were directly measured in baseline blood specimens of case subjects (n = 480) and the reference subcohort (n = 496). Risk associations were evaluated for total CVD (MI, IS, PAD, and CVD death), coronary and cerebrovascular disease (MI, IS, CVD death), and individual outcomes (MI, IS, and PAD). Models were adjusted for traditional risk factors, low-density lipoprotein cholesterol, and high-sensitivity C-reactive protein.

RESULTS

The risk of both composite outcomes significantly increased across quartiles of TRL-C and sdLDL-C. TRL-C was significantly associated with MI and PAD (MI hazard ratio [HR]_Q4: 3.05 [95% confidence interval (CI): 1.46 to 6.39]; p_trend = 0.002; PAD HR_Q4: 2.58 [95% CI: 1.18 to 5.63]; p_trend = 0.019), whereas sdLDL-C was significantly associated with MI alone (HR_Q4: 3.71 [95% CI: 1.59 to 8.63]; p_trend < 0.001). Both markers weakly associated with IS. Association patterns were similar for continuous exposures and, for TRL-C, among subjects with low atherogenic particle concentrations (apolipoprotein B <100 mg/dl).

CONCLUSIONS

TRL-C strongly associates with future MI and PAD events, whereas sdLDL-C strongly associates with MI alone. These findings signal that the cholesterol content of TRLs and sdLDL influence atherogenesis independently of low-density lipoprotein cholesterol, and high sensitivity C-reactive protein, with potentially different potency across vascular beds. (Women's Health Study; NCT00000479).

Pemafibrate prevents retinal neuronal cell death in NMDA-induced excitotoxicity via inhibition of p-c-Jun expression

Excitotoxicity is involved in the retinal neuronal cell death in diabetic retinopathy. Although fenofibrate has been shown to ameliorate the progression of diabetic retinopathy, the effect of pemafibrate, which is highly selective for peroxisome proliferator-activated receptor α on retinal neuronal cell death has not been documented. Here, we investigated whether pemafibrate exerts a beneficial effect against retinal ganglion cell (RGC) death induced by N-methyl-D-aspartate (NMDA) in rats. Experiments were performed on adult male Wistar rats that received an intravitreal injection of 20 nmol NMDA. Fluoro-Gold labeled RGC morphometry showed that oral intake of pemafibrate once a day for 7 days resulted in significant protection on RGC death induced by NMDA. Phosphorylated c-Jun protein, which is involved in apoptosis, was upregulated after NMDA exposure, and this increase was significantly lessened by the systemic pemafibrate treatment. Phosphorylated c-Jun immunopositive cells were colocalized with Thy-1 immunopositive cells, and the increased these cells were ameliorated by the pemafibrate treatment. An increase in TUNEL-positive cells was significantly suppressed by the pemafibrate treatment. Phosphorylated c-Jun immunopositive cells were colocalized with TUNEL-positive cells, and they were decreased by pemafibrate treatment. These results suggest that the RGC protection achieved with pemafibrate appears to be associated with inhibition of phosphorylated c-Jun and its anti-apoptotic effect.

Small-Molecule Modulation of PPARs for the Treatment of Prevalent Vascular Retinal Diseases

Vascular-related retinal diseases dramatically impact quality of life and create a substantial burden on the healthcare system. Age-related macular degeneration, diabetic retinopathy, and retinopathy of prematurity are leading causes of irreversible blindness. In recent years, the scientific community has made great progress in understanding the pathology of these diseases and recent discoveries have identified promising new treatment strategies. Specifically, compelling biochemical and clinical evidence is arising that small-molecule modulation of peroxisome proliferator-activated receptors (PPARs) represents a promising approach to simultaneously address many of the pathological drivers of these vascular-related retinal diseases. This has excited academic and pharmaceutical researchers towards developing new and potent PPAR ligands. This review highlights recent developments in PPAR ligand discovery and discusses the downstream effects of targeting PPARs as a therapeutic approach to treating retinal vascular diseases.

Marked effects of novel selective peroxisome proliferator-activated receptor α modulator, pemafibrate in severe hypertriglyceridemia: preliminary report

BACKGROUND

Currently available treatments have only been partly successful in patients with severe hypertriglyceridemia, including those with high serum triglycerides above 1,000 mg/dL (11.3 mmol/L), who often suffer from acute pancreatitis. Pemafibrate is a novel selective peroxisome proliferator-activated receptor α modulator (SPPARMα) which has been developed as an affordable oral tablet in Japan. We herein report the first three patients with severe hypertriglyceridemia who were successfully treated with pemafibrate.

METHODS

Three patients with fasting serum triglyceride (TG) levels above 1,000 mg/dL (11.3 mmol/L) were treated with pemafibrate (0.2-0.4 mg/day, 0.1-0.2 mg BID).

RESULTS

Serum TGs decreased from 2,000-3,000 mg/dL (22.6-33.9 mmol/L) to < 250 mg/dL (2.8 mmol/L) without adverse effects in all three patients. Serum TGs in Patient 1 and 2 decreased from 1,326 mg/dL (15.0 mmol/L) to 164 mg/dL (1.9 mmol/L) and from 2,040 mg/dL (23.1 mmol/L) to 234 mg/dL (2.6 mmol/L), respectively. Patient 3 with type 2 diabetes and 12.1% (109 mmol/mol) hemoglobin A1c had a TG level of 2,300 mg/dL (26.0 mmol/L). Even after glycemic control improved, TG remained high. After pemafibrate administration, TG decreased to 200 mg/dL (2.3 mmol/L). All patients showed no serious adverse events.

CONCLUSIONS

Pemafibrate demonstrated potential efficacy and safety for severe hypertriglyceridemia which may contribute to the prevention of acute pancreatitis, in a manner that can be easily prescribed and used as an oral tablet.

Prevalence of Dyslipidaemia among Type 2 Diabetes Mellitus Patients in the Western Cape, South Africa

Dyslipidaemia, an irregular aggregate of lipids in the blood is common in diabetes and cardiovascular disease sufferers. A cross-sectional study on the prevalence of dyslipidaemia was performed among type 2 diabetes mellitus (T2DM) patients in the Western Cape, South Africa. Patients (n = 100) that participated in the study were within the age range of 19-68 years, of whom 89% were observed to have serum lipid abnormalities. Out of the 100 patients, 56%, 64%, 61%, and 65% were recorded to have high total cholesterol (TC), hypertriglycemia, increased low-density lipoproteins cholesterol (LDL-C), and reduced high-density lipoproteins cholesterol (HDL-C), respectively. In male diabetic patients, a marked prevalence of (94%) dyslipidemia was noted, of which 52% were affected by high TC (5.3-7.9 mmol/L), with 70% having a high level of triglyceride (TG) [1.72-7.34 mmol/L], while 60% had a high LDL-C (3.1-5.5 mmol/L), including 78% with low HDL-C (0.7-1.1 mmol/L). In comparison, 84% of diabetic females had dyslipidemia, with high TC (5.1-8.1 mmol/L), hypertriglycemia (1.73-8.63 mmol/L), high LDL-C (3.1-5.6 mmol/L), and low levels of HDL-C (0.8-1.1 mmol/L) affecting 60%, 58%, 62%, and 52% of the patients, respectively. This study showed the importance of screening and the regular surveillance of dyslipidaemia in T2DM patients as there is a paucity of data on it in Africa.

Pemafibrate, a PPAR alpha agonist, attenuates neointima formation after vascular injury in mice fed normal chow and a high-fat diet

Recently, the prevention of cardiovascular events has become one of the most important aims of diabetes care. Peroxisome proliferator-activated receptor (PPAR) agonists have been reported to have vascular protective effects. Here, we examined whether pemafibrate, a selective PPAR alpha agonist, attenuated neointima formation after vascular injury and vascular smooth muscle cell (VSMC) proliferation. We performed endothelial denudation injury in mice treated with a high-fat diet (HFD) or normal chow. Orally administered pemafibrate significantly attenuated neointima formation after vascular injury in HFD and normal chow mice. Interestingly, pemafibrate increased the serum fibroblast growth factor 21 concentration and decreased serum insulin concentrations in HFD mice. In addition, body weight was slightly but significantly decreased by pemafibrate in HFD mice. Pemafibrate, but not bezafibrate, attenuated VSMC proliferation in vitro. The knockdown of PPAR alpha abolished the anti-VSMC proliferation effect of pemafibrate. BrdU assay results revealed that pemafibrate dose-dependently inhibited DNA synthesis in VSMCs. Flow cytometry analysis demonstrated that G1-to-S phase cell cycle transition was significantly inhibited by pemafibrate. Pemafibrate attenuated serum-induced cyclin D1 expression in VSMCs. However, apoptosis was not induced by pemafibrate as assessed by the TUNEL assay. Similar to the in vitro data, VSMC proliferation was also decreased by pemafibrate in mice. These data suggest that pemafibrate attenuates neointima formation after vascular injury and VSMC proliferation by inhibiting cell cycle progression.

PPARα Agonist Oral Therapy in Diabetic Retinopathy

Diabetic retinopathy (DR) is an eye condition that develops after chronically poorly-managed diabetes, and is presently the main cause for blindness on a global scale. Current treatments for DR such as laser photocoagulation, topical injection of corticosteroids, intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents and vitreoretinal surgery are only applicable at the late stages of DR and there are possibilities of significant adverse effects. Moreover, the forms of treatment available for DR are highly invasive to the eyes. Safer and more effective pharmacological treatments are required for DR treatment, in particular at an early stage. In this review, we cover recently investigated promising oral pharmacotherapies, the methods of which are safer, easier to use, patient-friendly and pain-free, in clinical studies. We especially focus on peroxisome proliferator-activator receptor alpha (PPARα) agonists in which experimental evidence suggests PPARα activation may be closely related to the attenuation of vascular damages, including lipid-induced toxicity, inflammation, an excess of free radical generation, endothelial dysfunction and angiogenesis. Furthermore, oral administration of selective peroxisome proliferator-activated receptor alpha modulator (SPPARMα) agonists may induce hepatic fibroblast growth factor 21 expression, indirectly resulting in retinal protection in animal studies. Our review will enable more comprehensive approaches for understanding protective roles of PPARα for the prevention of DR development.

Interaction between high-density lipoproteins and inflammation: Function matters more than concentration!

High-density lipoprotein (HDL) plays an important role in lipid metabolism and especially contributes to the reverse cholesterol transport pathway. Over recent years it has become clear that the effect of HDL on immune-modulation is not only dependent on HDL concentration but also and perhaps even more so on HDL function. This review will provide a concise general introduction to HDL followed by an overview of post-translational modifications of HDL and a detailed overview of the role of HDL in inflammatory diseases. The clinical potential of HDL and its main apolipoprotein constituent, apoA-I, is also addressed in this context. Finally, some conclusions and remarks that are important for future HDL-based research and further development of HDL-focused therapies are discussed.

Improved Prediction of the Drug-Drug Interactions of Pemafibrate Caused by Cyclosporine A and Rifampicin via PBPK Modeling: Consideration of the Albumin-Mediated Hepatic Uptake of Pemafibrate and Inhibition Constants With Preincubation Against OATP1B

Pemafibrate (PMF) is highly albumin-bound (>99.8%) and a substrate for hepatic uptake transporters (OATP1B) and CYP enzymes. Here, we developed a PBPK model of PMF to capture drug-drug interactions (DDI) incurred by cyclosporine (CsA) and rifampicin (RIF), the two OATP1B inhibitors. Initial PBPK modeling of PMF utilized in vitro hepatic uptake clearance (PS_inf) obtained in the absence of albumin, but failed in capturing the blood PMF pharmacokinetic (PK) profiles. Based on the results that in vitro PS_inf of unbound PMF was enhanced in the presence of albumin, we applied the albumin-facilitated dissociation model and the resulting PS_inf parameters improved the prediction of the blood PMF PK profiles. In refining our PBPK model toward improved prediction of the observed DDI data (PMF co-administered with single dosing of CsA or RIF; PMF following multiple RIF dosing), we adjusted the previously obtained in vivo OATP1B inhibition constants (K_i,OATP1B) of CsA or RIF for pitavastatin by correcting for substrate-dependency. We also incorporated the induction of OATP1B and CYP enzymes after multiple RIF dosing. Sensitivity analysis informed that the higher gastrointestinal absorption rate constant could further improve capturing the observed DDI data, suggesting the possible inhibition of intestinal ABC transporter(s) by CsA or RIF.

Management of hypertriglyceridemia

Hypertriglyceridemia is one of the most common lipid abnormalities encountered in clinical practice. Many monogenic disorders causing severe hypertriglyceridemia have been identified, but in most patients triglyceride elevations result from a combination of multiple genetic variations with small effects and environmental factors. Common secondary causes include obesity, uncontrolled diabetes, alcohol misuse, and various commonly used drugs. Correcting these factors and optimizing lifestyle choices, including dietary modification, is important before starting drug treatment. The goal of drug treatment is to reduce the risk of pancreatitis in patients with severe hypertriglyceridemia and cardiovascular disease in those with moderate hypertriglyceridemia. This review discusses the various genetic and acquired causes of hypertriglyceridemia, as well as current management strategies. Evidence supporting the different drug and non-drug approaches to treating hypertriglyceridemia is examined, and an easy to adopt step-by-step management strategy is presented.

Efficacy and safety of icosapent ethyl in hypertriglyceridaemia: a recap

Although low-density lipoprotein cholesterol lowering is effective in atherosclerotic cardiovascular disease (ASCVD) prevention, considerable ‘lipid-associated’ residual risk remains, particularly in patients with mild-to-moderate hypertriglyceridaemia (2–10 mmol/L; 176–880 mg/dL). Triglyceride (TG)-rich lipoproteins carry both TGs and cholesterol (remnant-cholesterol). At TG levels >5 mmol/L (440 mg/dL) vs. <1 mmol/L (88 mg/dL) or remnant-cholesterol >2.3 mmol/L (89 mg/dL) vs. <0.5 mmol/L (19 mg/dL), risk is ∼1.5-fold elevated for aortic stenosis, 2-fold for all-cause mortality, 3-fold for ischaemic stroke, 5-fold for myocardial infarction (MI), and 10-fold for acute pancreatitis. Furthermore, Mendelian randomization studies indicate that elevated TG-rich lipoproteins are causally related to increased risk of ASCVD and even all-cause mortality. While genetic and epidemiological data strongly indicate that TG-rich lipoproteins are causally linked to ASCVD, intervention data are ambiguous. Fibrates, niacin and low-dose omega-3 fatty acids have all been used in outcome trials, but have failed to demonstrate clear benefit in combination with statins. Whether the lack of additional benefit relates to methodological issues or true failure is indeterminate. Importantly, a recent intervention trial evaluating a high dose of eicosapentaenoic-acid showed clear benefit. Thus, REDUCE-IT evaluated the effect of icosapent ethyl (4 g/day) on cardiovascular outcomes in 8179 high-risk patients with moderate TG elevation on statin therapy. Over a median duration of 4.9 years, the relative risk for the primary endpoint (composite of cardiovascular death, non-fatal MI, non-fatal stroke, coronary revascularization, or unstable angina) was reduced by 25% (absolute risk 17.2% vs. 22.0%; P < 0.0001; number needed to treat 21). High-dose icosapent ethyl intervention therefore confers substantial cardiovascular benefit in high-risk patients with moderate hypertriglyceridaemia on statin therapy.

Association Between Triglycerides and Residual Cardiovascular Risk in Patients With Type 2 Diabetes Mellitus and Established Cardiovascular Disease (From the Bypass Angioplasty Revascularization Investigation 2 Diabetes [BARI 2D] Trial)

Triglyceride (TG) levels encompass several lipoproteins that have been implicated in atherogenic pathways. Whether TG levels independently associate with cardiovascular disease both overall and, in particular among patients with established coronary artery disease (CAD) and type 2 diabetes (T2DM), remains controversial. Data from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial was used to evaluate patients with T2DM and CAD. Cox proportional hazards models were used to determine the association between TG levels and outcomes. Stepwise adjustment was performed for demographics, clinical factors, lipid profile and statin treatment. The primary composite outcome was time to CV death, myocardial infarction (MI), or stroke and secondary outcome was CV death. Among 2,307 patients with T2DM and CAD, the mean (±SD) TG levels were 181 (±136) with a median (Q1-Q3) 148mg/dL (104-219). Overall, 51% of patients had TG <150 mg/dL, 18% 150-199 mg/dL, 28% 200-499 mg/dL and 3% ≥500 mg/dL. Participants with elevated TG levels (≥150 mg/dL) were younger (61 vs 63 years, p <0.001), had higher BMI (32 vs 30 kg/m², p <0.001), more likely to have had prior MI (34.2 vs 30.1%, p = 0.033) and revascularization (25.8 vs 21.4%, p = 0.013), had lower HDL-C (34 vs 39 mg/dL, p <0.001) and higher HbA1c (8 vs 7%, p <0.001). In unadjusted analyses, baseline TG levels were linearly associated with both the primary composite and secondary outcomes. In fully adjusted analyses, every 50 mg/dL increase in TG level was associated with a 3.8% (HR 1.038, 95%CI 1.004-1.072, p <0.001) increase in the primary composite outcome and a 6.4% (HR 1.064 95%CI 1.018-1.113, p <0.001) increase in the secondary outcome. There was no interaction between TG and outcomes within key subgroups including female sex, additional non-coronary atherosclerotic disease, CKD or low LDL (<100 mg/dL). In conclusion, among patients with T2DM and CAD, elevated TG were independently associated with adverse cardiovascular outcomes, even after adjustment for clinical and simple biochemical covariates.

Apolipoprotein B48 metabolism in chylomicrons and very low-density lipoproteins and its role in triglyceride transport in normo- and hypertriglyceridemic human subjects

BACKGROUND

Renewed interest in triglyceride-rich lipoproteins as causative agents in cardiovascular disease mandates further exploration of the integrated metabolism of chylomicrons and very low-density lipoproteins (VLDL).

METHODS

Novel tracer techniques and an integrated multi-compartmental model were used to determine the kinetics of apoB48- and apoB100-containing particles in the chylomicron and VLDL density intervals in 15 subjects with a wide range of plasma triglyceride levels.

RESULTS

Following a fat-rich meal, apoB48 appeared in the chylomicron, VLDL₁ and VLDL₂ fractions in all subjects. Chylomicrons cleared rapidly from the circulation but apoB48-containing VLDL accumulated, and over the day were 3-fold higher in those with high versus low plasma triglyceride. ApoB48-containing particles were secreted directly into both the chylomicron and VLDL fractions at rates that were similar across the plasma triglyceride range studied. During fat absorption, whilst most triglyceride entered the circulation in chylomicrons, the majority of apoB48 particles were secreted into the VLDL density range.

CONCLUSION

The intestine secretes apoB48-containing particles not only as chylomicrons but also directly into the VLDL₁ and VLDL₂ density ranges both in the basal state and during dietary lipid absorption. Over the day, apoB48-containing particles appear to comprise about 20-25% of circulating VLDL and, especially in those with elevated triglycerides, form part of a slowly cleared 'remnant' particle population, thereby potentially increasing CHD risk. These findings provide a metabolic understanding of the potential consequences for increased CHD risk when slowed lipolysis leads to the accumulation of remnants, especially in individuals with hypertriglyceridemia.

Impact of expanded FDA indication for icosapent ethyl on enhanced cardiovascular residual risk reduction

Hypertriglyceridemia is associated with increased cardiovascular disease (CVD) risk. The Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) demonstrated that the purified, stable ethyl ester of eicosapentaenoic acid, icosapent ethyl (IPE), added to statins reduced CVD events by 25% (p < 0.001), leading to an expanded indication in the USA. IPE is now approved as an adjunct to maximally tolerated statins to reduce CVD event risk in adults with triglyceride (TG) levels ≥150 mg/dl and either established CVD or diabetes mellitus plus ≥2 additional CVD risk factors. The new indication allows co-administration of IPE for elevated TG levels with statin treatment, enabling effective residual risk reduction in a broader at-risk population beyond what can be achieved with intensive low-density lipoprotein cholesterol control alone.

Pemafibrate decreases markers of hepatic inflammation in patients with non-alcoholic fatty liver disease

AIM OF THE STUDY

Non-alcoholic fatty liver disease (NAFLD) is frequently complicated by dyslipidemia and is considered to be a hepatic manifestation of metabolic syndrome. Pemafibrate is a novel selective peroxisome proliferator-activated receptor-α modulator. There are no reports of the clinical effects of pemafibrate in patients with NAFLD. The aim of this study is to determine the effect of pemafibrate on patients with NAFLD.

MATERIAL AND METHODS

This is an observational study of patients with NAFLD complicated by dyslipidemia treated with pemafibrate for three months. Patient medical records were retrospectively reviewed.

RESULTS

Thirty-eight patients were included, and all patients had dyslipidemia without diabetes. Changes in parameters after three months of pemafibrate therapy were evaluated. Weight was not significantly changed. Alanine aminotransferase, a marker of hepatic inflammation, significantly improved. Remarkably, alkaline phosphatase and γ-glutamyl transpeptidase decreased in all patients. The albumin-bilirubin score, a marker of hepatic function, improved due to significant elevation of serum albumin and decrease in total bilirubin. Lipid profiles including high-density lipoprotein cholesterol and triglycerides significantly decreased. Low-density lipoprotein cholesterol did not significantly change. The NAFLD fibrosis score significantly improved, but the FIB-4 index did not significantly change.

CONCLUSIONS

Three months of pemafibrate treatment of patients with NAFLD improves markers of hepatic inflammation, function and fibrosis. This is the first clinical study evaluating the effect of pemafibrate in patients with NAFLD.

Targeting hypertriglyceridemia to mitigate cardiovascular risk: A review

A causal relationship between elevated triglycerides and cardiovascular disease is controversial, as trials of triglyceride-lowering treatments have not shown significant impact on cardiovascular outcomes. However, hypertriglyceridemia is associated with atherogenesis and risk for acute cardiovascular events that persist despite optimal statin treatment. Although most trials of triglyceride-lowering treatments have been negative, in trials of niacin and fibrates, subgroup analyses in patients with higher baseline triglycerides and lower HDL-C levels suggest reduced incidence of cardiovascular endpoints. The REDUCE-IT trial demonstrated that addition of purified prescription eicosapentaenoic acid (icosapent ethyl) 4 ​g/day in high-risk patients with triglyceride levels 135-499 ​mg/dL and optimized statin treatment significantly reduced cardiovascular events versus placebo (hazard ratio 0.75; 95% confidence interval 0.68-0.83; P ​< ​0.001). Benefit was seen regardless of baseline and on-treatment triglyceride levels, suggesting that other effects of eicosapentaenoic acid besides triglyceride reduction may have played a role.

Efficacy and safety of add on therapies in patients with hypercholesterolemia undergoing statin therapy

INTRODUCTION

Statins are the first-line treatment to reduce cardiovascular (CV) events, mainly by reducing low-density-lipoprotein cholesterol (LDL-C), but many patients need additional treatments to reach the current lipid goals.

AREAS COVERED

Herein, the authors review the published literature on the efficacy and safety of the therapies that are most often added to statins to achieve lipid targets.

EXPERT OPINION

Ezetimibe is usually the first additional treatment to achieve LDL-C targets. It reduces LDL-C by about a further 20% and has an excellent safety and tolerability profile. The monoclonal antibody proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, evolocumab, and alirocumab, can reduce LDL-C by ≥50% when added to statins and they also have a well-established safety and tolerability record. The recently approved bempedoic acid is well tolerated and appears to be free of skeletal muscle-related problems, but the CV outcome study with this drug has not been completed. Inclisiran, a small-interfering RNA targeting PCSK9 is at an advanced stage of development and the available data indicate a satisfactory safety profile and LDL-C lowering efficacy similar to the PCSK9 monoclonal antibodies with the advantage of less frequent administration.

When to lower triglycerides?

PURPOSE OF REVIEW

Substantial risk of ASCVD events persists despite intensive statin therapy and other agents to lower LDL-C. The optimal way to address other elements of dyslipidemia, such as triglyceride-rich particles (TRL) and when to treat has remained unclear.

RECENT FINDINGS

Several lines of evidence indicate that TRL are associated with atherogenesis, partly because of associated factors, such as cholesterol-enriched remnant particles, high LDL particle number, high apo-B, high apo-CIII, and others. High triglyceride is increasingly prevalent because of worsening of lifestyle factors, obesity, and diabetes. Trials with fibrates, and niacin to reduce residual dyslipidemia have not provided evidence of benefits after statin therapy, thus far. A recent trial with an omega 3 fatty acid (OM3FA), icosapent-ethyl (IPE), provided evidence for a 25% reduction in ASCVD events in statin-treated high-risk population. These results were unexplained by triglyceride reduction alone, and are likely related to unique biologic effects of IPE on atherosclerosis. Finally, in patients with very high triglycerides, lifestyle measures and several triglyceride-lowering agents are indicated, often in combination, to prevent episodes of pancreatitis. A novel Apo C-III inhibitor may provide additional benefit in such patients.

SUMMARY

There is evidence for the benefits of IPE in preventing ASCVD events. A novel fibrate is in clinical trials.

Selective Peroxisome Proliferator-Activated Receptor Alpha Modulators (SPPARMα): New Opportunities to Reduce Residual Cardiovascular Risk in Chronic Kidney Disease?

PURPOSE OF REVIEW

Chronic kidney disease (CKD) poses a major global challenge, which is exacerbated by aging populations and the pandemic of type 2 diabetes mellitus. Much of the escalating burden of CKD is due to cardiovascular complications. Current treatment guidelines for dyslipidemia in CKD prioritize low-density lipoprotein cholesterol management, but still leave a high residual cardiovascular risk. Targeting elevated triglycerides and low plasma high-density lipoprotein cholesterol, a common feature of CKD, could offer additional benefit. There are, however, safety issues with current fibrates (peroxisome proliferator-activated receptor alpha [PPARα] agonists), notably the propensity for elevation in serum creatinine, indicating the need for new approaches.

RECENT FINDINGS

Interactions between the ligand and PPARα receptor influence the specificity and potency of receptor binding, and downstream gene and physiological effects. The peroxisome proliferator-activated receptor alpha modulator (SPPARMα) concept aims to modulate the ligand structure so as to enhance binding at the PPARα receptor, thereby improving the ligand's selectivity, potency, and safety profile. This concept has led to the development of pemafibrate, a novel SPPARMα agent. This review discusses evidence that differentiates pemafibrate from current fibrates, especially the lack of evidence for elevation in serum creatinine or worsening of renal function in high-risk patients, including those with CKD. Differentiation of pemafibrate from current fibrates aims to address unmet clinical needs in CKD. The ongoing PROMINENT study will provide critical information regarding the long-term efficacy and safety of pemafibrate in patients with type 2 diabetes mellitus, including those with CKD, and whether the favorable lipid-modifying profile translates to reduction in residual cardiovascular risk.

Peroxisome Proliferator-Activated Receptors and Their Novel Ligands as Candidates for the Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a major health issue worldwide, frequently associated with obesity and type 2 diabetes. Steatosis is the initial stage of the disease, which is characterized by lipid accumulation in hepatocytes, which can progress to non-alcoholic steatohepatitis (NASH) with inflammation and various levels of fibrosis that further increase the risk of developing cirrhosis and hepatocellular carcinoma. The pathogenesis of NAFLD is influenced by interactions between genetic and environmental factors and involves several biological processes in multiple organs. No effective therapy is currently available for the treatment of NAFLD. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that regulate many functions that are disturbed in NAFLD, including glucose and lipid metabolism, as well as inflammation. Thus, they represent relevant clinical targets for NAFLD. In this review, we describe the determinants and mechanisms underlying the pathogenesis of NAFLD, its progression and complications, as well as the current therapeutic strategies that are employed. We also focus on the complementary and distinct roles of PPAR isotypes in many biological processes and on the effects of first-generation PPAR agonists. Finally, we review novel and safe PPAR agonists with improved efficacy and their potential use in the treatment of NAFLD.

Contribution of remnant cholesterol to cardiovascular risk

BACKGROUND

Remnant cholesterol in triglyceride-rich lipoproteins is associated observationally and genetic, causally with increased risk of atherosclerotic cardiovascular disease in healthy individuals.

OBJECTIVES

We tested the hypothesis that an unmet medical need exists in individuals with high nonfasting remnant cholesterol and prior atherosclerotic cardiovascular disease.

METHODS

From amongst 109 574 individuals in a prospective cohort study of the Danish general population, we included 2973 individuals aged 20-80 with baseline diagnoses of myocardial infarction/ischaemic stroke ascertained from national Danish health registries.

RESULTS

The recurrent major cardiovascular event (MACE) incidence rates per 1000 person-years were 39 (95% confidence interval: 30-50) for individuals with remnant cholesterol levels ≥ 1.5 mmol L^-1 (≥58 mg dL^-1 ), 31 (26-37) for 1-1.49 mmol L^-1 (39-57 mg dL^-1 ), 27 (24-31) for 0.5-0.99 mmol L^-1 (19-38 mg dL^-1 ) and 23 (19-27) for individuals with remnant cholesterol < 0.5 mmol L^-1 (<19 mg dL^-1 ). Compared to individuals with remnant cholesterol < 0.5 mmol L^-1 (<19 mg dL^-1 ), the subhazard ratio for recurrent MACE was 1.23 (95% CI: 0.98-1.55) for individuals with remnant cholesterol levels of 0.5-0.99 mmol L^-1 (19-38 mg dL^-1 ), 1.48 (1.14-1.92) for 1-1.49 mmol L^-1 (39-57 mg dL^-1 ) and 1.79 (1.28-2.49) for ≥ 1.5 mmol L^-1 (≥58 mg dL^-1 ). The recurrent MACE incidence rates per 1000 person-years for individuals with remnant cholesterol levels < 0.5 mmol L^-1 (<19 mg dL^-1 ) and ≥ 1.5 mmol L^-1 (≥58 mg dL^-1 ) were 10 (6.6-15) and 31 (21-47) for those below age 65 and correspondingly 25 (21-30) and 43 (32-59) for those with LDL cholesterol levels < 3 mmol L^-1 (<116 mg dL^-1 ), respectively. For a 20% recurrent MACE risk reduction in secondary prevention, an estimated remnant cholesterol lowering of 0.83 mmol L^-1 (32 mg dL^-1 ) would be needed.

CONCLUSIONS

In individuals with a diagnosis of myocardial infarction/ischaemic stroke, a lower remnant cholesterol of 0.8 mmol L^-1 (32 mg dL^-1 ) was estimated to reduce recurrent MACE by 20% in secondary prevention. Our data indicate an unmet medical need for secondary prevention in individuals with high nonfasting remnant cholesterol levels.

Pemafibrate Tends to have Better Efficacy in Treating Dyslipidemia than Fenofibrate

AIMS

To compare the efficacy of pemafibrate (PF) and fenofibrate (FF) in treating dyslipidemia.

METHODS

A comprehensive search was performed on the public database to identify relevant randomized controlled trials (RCTs), which compared the effects of PF and FF treatment in lipid parameters among patients with dyslipidemia. Mean difference (MD) and 95% confidence intervals (CI) were pooled for continuous outcomes, whereas odds ratio (OR) and 95% CI were calculated for dichotomous outcomes.

RESULTS

Three RCTs were included with a total of 744 patients (PF=547 and FF=197). Compared with the FF group (100mg/day), PF group (0.05 to 0.4mg/day) had a better effect on reducing triglycerides (TGs) (MD, -8.66; 95%CI, -10.91 to -6.41), very low-density lipoprotein cholesterol (VLDL-C, MD, -12.19; 95%CI, -15.37 to - 9.01), remnant lipoprotein cholesterol (MD, -13.16; 95%CI, -17.62 to -8.69), apolipoprotein-B48 (ApoB48, MD, -12.74; 95%CI, -17.71 to -7.76) and ApoCIII (MD, -6.25; 95%CI, -11.85 to -0.64). Although a slightly LDL-Cincreasing effect was found in PF-treated group (MD, 3.10; 95%CI, -0.12 to 6.09), the levels of HDL-C (MD, 3.59; 95%CI, 1.65 to 5.53) and ApoAI (MD, 1.60; 95%CI, 0.38 to 2.82) were significantly increased in the PF group. However, no significant difference was found in the level of total cholesterol (MD, 0.01; 95%CI, -1.37 to - 1.39), non-HDL-C (MD, -0.06; 95%CI, -1.75 to 1.63), ApoB (MD, 0.39; 95%CI, -1.37 to 2.15) and ApoAII (MD, 3.31; 95%CI, -1.66 to 8.29) between the two groups. In addition, the incidence of total adverse events (OR, 0.68; 95%CI, 0.53 to 0.86) and adverse drug reactions (OR, 0.36; 95%CI, 0.24 to 0.54) was lower in the PF group than that in the FF group.

CONCLUSIONS

Pemafibrate tends to have better efficacy in treating dyslipidemia than fenofibrate.

Targeting apoC-III and ANGPTL3 in the treatment of hypertriglyceridemia

INTRODUCTION

The prevalence of hypertriglyceridemia (HTG) is increasing. Elevated triglyceride (TG) levels are associated with an increased cardiovascular disease (CVD) risk. Moreover, severe HTG results in an elevated risk of pancreatitis, especially in severe HTG with an up to 350-fold increased risk. Both problems emphasize the clinical need for effective TG lowering.

AREAS COVERED

The purpose of this review is to discuss the currently available therapies and to elaborate the most promising novel therapeutics for TG lowering.

EXPERT OPINION

Conventional lipid lowering strategies do not efficiently lower plasma TG levels, leaving a residual CVD and pancreatitis risk. Both apolipoprotein C-III (apoC-III) and angiopoietin-like 3 (ANGPTL3) are important regulators in TG-rich lipoprotein (TRL) metabolism. Several novel agents targeting these linchpins have ended phase II/III trials. Volanesorsen targeting apoC-III has shown reductions in plasma TG levels up to 90%. Multiple ANGPLT3 inhibitors (evinacumab, IONIS-ANGPTL3-L_Rx, ARO-ANG3) effectuate TG reductions up to 70% with concomitant potent reduction in all other apoB containing lipoprotein fractions. We expect these therapeutics to become players in the treatment for (especially) severe HTG in the near future.

Triglycerides and ASCVD Risk Reduction: Recent Insights and Future Directions

PURPOSE OF REVIEW

This review focuses on recent evidence examining the role triglycerides (TG) and triglyceride-enriched lipoproteins (TGRL) play in atherosclerotic cardiovascular disease (ASCVD). It also provides a succinct overview of current and future TG-lowering therapies for ASCVD risk reduction.

RECENT FINDINGS

Epidemiological and Mendelian randomization studies have consistently shown that TGRL are strongly associated with ASCVD. REDUCE-IT demonstrated cardiovascular benefit with icosapent ethyl in high-risk patients with hypertriglyceridemia on statin therapy. Polymorphisms in APOC3 and ANGPTL3 are associated with ASCVD and use of RNA-interfering therapies to target these proteins has shown TG lowering in early phase trials. TG and TGRL are causally associated with ASCVD. Lifestyle modifications and statin therapy can lower TG/TGRL and are considered first-line treatment for hypertriglyceridemia. Icosapent ethyl has been shown to reduce residual ASCVD risk in high-risk patients on maximally tolerated statins. Ongoing clinical trials will better define optimal therapy for patients on statins with residual hypertriglyceridemia.

Remnant lipoproteins: are they equal to or more atherogenic than LDL?

PURPOSE OF REVIEW

To critically appraise new insights into the biology of remnant lipoproteins and their putative role in the pathophysiology of atherosclerotic cardiovascular disease, and to compare the atherogenicity of remnant particles with that of low-density lipoproteins (LDL).

RECENT FINDINGS

New in-vivo stable isotope tracer studies of the kinetics of apoB48 and apoB100-containing lipoproteins in postprandial conditions have revealed that apoB48-containing very low-density lipoproteins (VLDL) accumulated markedly in hypertriglyceridemic patients. These intestinally-derived particles were cleared slowly, and represented up to 25% of circulating VLDL; as part of the remnant particle population, they may increase cardiovascular risk. Importantly, the PCSK9 inhibitor, evolocumab, was shown to reduce remnant levels (-29%) during the postprandial period in diabetic patients on statin therapy - an effect which may be additive to that of LDL-cholesterol reduction in conferring cardiovascular benefit. In recent Mendelian randomization studies, the effect of lowering triglyceride-rich lipoproteins or LDL-cholesterol translated to similar clinical benefit per unit of apoB. Finally, in randomized trials involving statin-treated patients with atherosclerotic cardiovascular disease, remnant cholesterol levels were associated with coronary atheroma progression independently of LDL-cholesterol.

SUMMARY

Overall, data from observational studies in large cohorts, Mendelian randomization studies, meta-regression analyses, and post-hoc analyses of randomized trials are consistent with the contention that remnants are highly atherogenic particles and contribute to the atherosclerotic burden in an equivalent manner to that of LDL.

Novel emerging therapies in atherosclerosis targeting lipid metabolism

INTRODUCTION

Recent years have brought significant developments in lipid and atherosclerosis research. Although statins are a cornerstone in hyperlipidemia management, new non-statin therapies have had an impact. The reduction of low-density lipoprotein cholesterol (LDL-C) further translates into the lowering of cardiovascular mortality. Additionally, lipid research has progressed beyond LDL-C reduction and this has brought triglyceride (TG) and other apoprotein-B containing lipids into focus.

AREAS COVERED

Inclisiran and pemafibrate, with expected approval soon, come under the spotlight. We discuss other therapeutics such as lomitapide, mipomersen, volanesorsen, and evinacumab and newly approved non-statin-based therapies such as ezetimibe, icosapent ethyl (IPE), and bempedoic acid.

EXPERT OPINION

New options now exist for the prevention of atherosclerosis in patients that are not optimized on statin therapy. Multiple guidelines endorse ezetimibe, PCSK9 inhibitors, bempedoic, and IPE as add-on therapy. Recently approved bempedoic acid/ezetimibe combination might gain popularity among clinicians. Inclisiran and pemafibrate show promise in the reduction of LDL-C and TG, respectively, and results are pending in cardiovascular outcome trials. Combination strategies could improve outcomes, but the challenge will be balancing cost and selecting the correct patient population for each treatment modality to maximize benefit with the fewest medications.

Postprandial hyperlipidemia as a risk factor in patients with type 2 diabetes

Introduction: Postprandial hyperlipidemia is a common feature of the atherogenic dyslipidemia in patients with type 2 diabetes. Quantification of this with oral fat tolerance tests is not used routinely in clinical practice and abnormal postprandial lipids are usually inferred from non-fasting plasma triglyceride levels. Identifying excessive postprandial hyperlipidemia may help to refine cardiovascular risk assessment but there are no treatments currently available which selectively target postprandial lipids and no large cardiovascular outcome trials using this as the entry criterion.Areas covered: In this review of relevant published material, we summarize the findings from the most important publications in this area.Expert opinion: Postprandial hyperlipidemia appears to contribute to the cardiovascular risk in patients with diabetes. Non-fasting triglyceride levels provide a surrogate marker of postprandial hyperlipidemia but more specific markers such as apoB48 levels may prove to be more reliable. Omega-3 fatty acids, fibrates and ezetimibe can reduce postprandial lipids but may not correct them completely. Several novel treatments have been developed to target hypertriglyceridemia and some of these may be particularly effective in improving postprandial levels. Further clinical trials are needed to establish the role of postprandial lipids in assessment of cardiovascular risk and to identify the most effective treatments.

Emerging Mechanisms of Cardiovascular Protection for the Omega-3 Fatty Acid Eicosapentaenoic Acid

Patients with well-controlled LDL (low-density lipoprotein) levels still have residual cardiovascular risk associated with elevated triglycerides. Epidemiological studies have shown that elevated fasting triglyceride levels associate independently with incident cardiovascular events, and abundant recent human genetic data support the causality of TGRLs (triglyceride-rich lipoproteins) in atherothrombosis. Omega-3 fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower blood triglyceride concentrations but likely exert additional atheroprotective properties at higher doses. Omega-3 fatty acids modulate T-cell differentiation and give rise to various prostaglandins and specialized proresolving lipid mediators that promote resolution of tissue injury and inflammation. The REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial) with an EPA-only formulation lowered a composite of cardiovascular events by 25% in patients with established cardiovascular disease or diabetes mellitus and other cardiovascular risk factors. This clinical benefit likely arises from multiple molecular mechanisms discussed in this review. Indeed, human plaques readily incorporate EPA, which may render them less likely to trigger clinical events. EPA and DHA differ in their effects on membrane structure, rates of lipid oxidation, inflammatory biomarkers, and endothelial function as well as tissue distributions. Trials that have evaluated DHA-containing high-dose omega-3 fatty acids have thus far not shown the benefits of EPA alone demonstrated in REDUCE-IT. This review will consider the mechanistic evidence that helps to understand the potential mechanisms of benefit of EPA.

Novel therapeutics in hypertriglyceridaemia and chylomicronaemia

Currently there is evidence on hypertriglyceridaemia as an independent risk factor of atherosclerosis. Chylomicronaemia associated with very high concentration of triglycerides may cause severe and recurrent acute pancreatitis. The cause of most cases is a combination of a polygenetic basis with some lifestyles and pathological conditions. Some rare and familial chylomicronaemias are mendelian diseases with an autosomal recessive pattern. On the other hand, plasma triglycerides have considerable biological variability and usually descend with non-pharmacological interventions alone. In some cases, drugs are also required for their control, but their impact on vascular risk reduction or pancreatitis prevention is more controversial. The recent advances in knowledge of molecular lipid metabolism and pharmacological technologies are resulting in the development of new therapeutic strategies, which can be applied to patients with refractory hypertrigliceridaemia. The challenge may be how the health systems can cover its high costs.

Prevalence of US Adults with Triglycerides ≥ 150 mg/dl: NHANES 2007-2014

Introduction

Hypertriglyceridemia is associated with increased atherosclerotic cardiovascular disease (ASCVD) event risk, which persists even in statin-treated patients. The objective of this analysis was to estimate the prevalence of triglyceride (TG) levels ≥ 150 mg/dl in statin-treated adults with diabetes or ASCVD in the United States.

Methods

Laboratory data, medical history, and prescription data from 40,617 subjects who participated in the US National Health and Nutrition Examination Survey (NHANES) spanning 8 years (four 2-year surveys; 2007–2014) were analyzed. Patients included were ≥ 20 years old and had morning fasting (at least 8.5 h) TG values available. The proportion and weighted number of individuals in the US population with TG ≥ 150 mg/dl was calculated according to statin use, as well as in key subgroups of statin-treated patients including those with low-density lipoprotein cholesterol (LDL-C) levels < 100 mg/dl, type 2 diabetes, ASCVD, and those with type 2 diabetes and ASCVD.

Results

A total of 9593 subjects, projected to represent 219.9 million Americans, met the study entry criteria and were included in the analysis. Of these, 2523 had TG levels ≥ 150 mg/dl, translating to a prevalence of 25.9% and representing 56.9 million Americans. Among statin-treated adults, the proportion with TG levels ≥ 150 mg/dl was 31.6% (12.3 million) and ranged from 27.6 to 39.5% for those who also had LDL-C levels < 100 mg/dl and type 2 diabetes or ASCVD.

Conclusions

Over 12 million Americans are treated with a statin and have TG levels ≥ 150 mg/dl. Interventions such as icosapent ethyl that have been shown to reduce ASCVD event risk in this elevated TG population with type 2 diabetes or established ASCVD can provide substantial clinical benefit for these patients.

Cardiovascular risk reduction with icosapent ethyl

PURPOSE OF REVIEW

Residual risk for atherosclerotic cardiovascular disease (ASCVD) persists even among patients with optimal low-density lipoprotein cholesterol (LDL-C) levels. Randomized trials attempting to modulate other lipids beyond LDL-C have failed to demonstrate significant reductions in ischemic events.

RECENT FINDINGS

Mounting evidence suggests that triglyceride elevation is an independent risk factor for ASCVD. Though trials of triglyceride-lowering therapy in the statin era have failed to provide protection from ASCVD events, subgroup analyses have revealed that those with the highest triglycerides at time of enrollment appeared to receive the greatest clinical benefit. REDUCE-IT was a trial that enrolled patients with high triglycerides despite having goal LDL-C levels on statin therapy. Treatment with icosapent ethyl, a highly purified omega-3 fatty acid (OM3FA), eicosapentaenoic acid ethyl ester, provided a 25% relative risk reduction for the primary composite cardiovascular endpoint (hazard ratio 0.75, 95% CI 0.68--0.83; P = 0.00000001), as well as a 30% relative risk reduction in total ischemic events (P = 0.00000000036).

SUMMARY

Icosapent ethyl was rigorously shown to decrease residual risk for cardiovascular events, though the benefits seen were likely because of mechanisms beyond mere triglyceride lowering. Clinical application of icosapent ethyl in this cohort of patients with residual risk is urgently needed.

Pharmacokinetics of current and emerging treatments for hypercholesterolemia

Introduction: Reduction of low-density-lipoprotein cholesterol (LDL-C) and other apolipoprotein B (apoB)-containing lipoproteins reduces cardiovascular (CV) events and greater reductions have greater benefits. Current lipid treatments cannot always achieve desirable LDL-C targets and additional or alternative treatments are often needed.Areas covered: In this article, we review the pharmacokinetics of the available and emerging treatments for hypercholesterolemia and focus on recently approved drugs and those at a late stage of development.Expert opinion: Statin pharmacokinetics are well known and appropriate drugs and doses can usually be chosen for individual patients to achieve LDL-C targets and avoid adverse effects and drug-drug interactions. Ezetimibe, icosapent ethyl and the monoclonal antibodies evolocumab and alirocumab have established efficacy and safety. Newer oral agents including pemafibrate and bempedoic acid have generally favorable pharmacokinetics supporting use in a wide range of patients. RNA-based therapies with antisense oligonucleotides are highly specific for their targets and those inhibiting apoB, apoCIII, angiopoietin-like protein 3 and lipoprotein(a) have shown promising results. The small-interfering RNA inclisiran has the notable advantage that a single subcutaneous administration may be effective for up to 6 months. The CV outcome trial results and long term safety data are eagerly awaited for these new agents.

Triglycerides and residual risk

PURPOSE OF REVIEW

To review the recent evidence from observational/genetic/interventional studies addressing triglycerides and residual cardiovascular risk (CVRisk).

RECENT FINDINGS

Large population-based and secondary prevention studies consistently show an association of higher triglycerides with increased CVRisk. This is compounded by genetic studies demonstrating an independent relationship between triglyceride raising or lowering genetic variants affecting triglyceride-rich lipoproteins (TRL) metabolism and CVRisk. Mendelian randomization analysis suggests the benefit of genetic lowering of triglycerides and LDL-cholesterol is similar per unit change in apolipoprotein-B. Among cholesterol-lowering trials, more intensive statin therapy produced greater CVRisk reductions in patients with higher TRL-cholesterol or triglycerides; proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition led to similar triglycerides reduction but greater non-HDL-C or apolipoprotein-B reductions than fibrates or fish oils. Regarding n-3 fatty acids, A Study of Cardiovascular Events in Diabetes (ASCEND) and Vitamin D and Omega-3 Trial (VITAL) primary prevention trials with eicosapentaenoic acid (EPA) and docosahexaenoic acid failed to demonstrate cardiovascular benefits, Conversely, Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) using high-dose icosapent-ethyl (purified EPA) in primary (diabetes) and secondary prevention with hypertriglyceridemia showed significant cardiovascular events reductions (greater than expected by the observed triglycerides or apolipoprotein-B reductions, suggesting potential benefits through non-lipid pathways).

SUMMARY

Evidence suggests higher triglycerides are a marker of CVRisk and may help identify patients who benefit from intensification of therapy. Moreover, genetic studies support a causal link between TRL/triglycerides and cardiovascular disease. Treatment with high-dose EPA may be of benefit in high-risk patients with hypertriglyceridemia to reduce CVRisk.

Fibrates Revisited: Potential Role in Cardiovascular Risk Reduction

Fibrates, peroxisome proliferator-activated receptor-α agonists, are potent lipid-modifying drugs. Their main effects are reduction of triglycerides and increase in high-density lipoprotein levels. Several randomized controlled trials have not demonstrated their benefits on cardiovascular risk reduction, especially as an "add on" to statin therapy. However, subsequent analyses by major clinical trials, meta-analyses, and real-world evidence have proposed their potential in specific patient populations with atherogenic dyslipidemia and metabolic syndrome. Here, we have reviewed and discussed the accumulated data on fibrates to understand their current status in cardiovascular risk management.

Current and new pharmacotherapy options for non-alcoholic steatohepatitis

INTRODUCTION

There is an unmet medical need for an effective anti-fibrotic treatment for NASH with advanced fibrosis.

AREAS COVERED

The authors review the current and novel agents for the treatment of NASH with fibrosis. They also consider the potential future strategies of combination therapies.

EXPERT OPINION

Farnesoid X receptor (FXR) agonist (obeticholic acid [OCA]) significantly ameliorated hepatic fibrosis in NASH stage 2/3 fibrosis in an interim analysis of phase 3 trial. Because OCA has several drawbacks such as itching and elevated low-density lipoprotein-cholesterol (LDL-C), non-bile acid FXR agonists are now under development. Selonsertib (apoptosis signaling kinase 1 inhibitor), emricasan (an irreversible pan-caspase inhibitor), and simtsuzumab (a monoclonal antibody against lysyl oxidase-like 2) were discontinued because of no efficacy over placebo. Peroxisome proliferator-activator receptor α/δ agonists, C-C motif chemokine receptor-2/5 antagonists, and thyroid β receptor agonist are ongoing in phase 3 trials. A variety of agents including fibroblast growth factor (FGF)-21 and FGF-19 agonists, as well as acetyl-CoA carboxylase inhibitors, are also expected. Among antidiabetic agents, semaglutide, a novel GLP-1 RA, is ongoing for NASH stage 1-3 fibrosis in a phase 2 trial. Furthermore, the combination of GLP-RA/glucagon receptor agonist and GLP-RA/gastrointestinal peptide agonist are promising future options.

Experimental Therapeutics for Challenging Clinical Care of a Patient with an Extremely Rare Homozygous APOC2 Mutation

Background

Among many causes of hypertriglyceridemia (HTG), familial chylomicronemia syndrome (FCS) is a rare monogenic disorder that manifests as severe HTG and acute pancreatitis. Among the known causal genes for FCS, mutations in APOC2 only account for <2% of cases. Medical nutrition therapy is critical for FCS because usual triglyceride- (TG-) lowering medications are ineffective. Therapeutic plasma exchange (TPE) with fresh frozen plasma (FFP) is an option to urgently reduce TG and pancreatitis episodes. Several novel biologics are under development to treat HTG and may provide therapeutic options for FCS in the future.

Objective

We present the challenging care of a 43-year-old man with FCS with apoC-II deficiency and the results of two types of TPE and of investigational TG-lowering biologic therapies.

Results

The patient's lipid profile was consistent with FCS. A novel homozygous variant was identified in APOC2, and its pathogenicity was confirmed. Even on a fat-restricted diet, his care was tremendously complicated with unremitting bouts of pancreatitis. TPE with FFP replacement lowered TG >90% post-sessions and appeared to reduce pancreatitis episodes. Experimental ANGPTL3 and APOC3 inhibitors each lowered TG by >50%.

Conclusions

Our case demonstrates the importance of delineating and defining the underlying etiology of a rare disorder to optimize therapy and to minimize unfavorable outcomes.

Legacy effect of fibrate add-on therapy in diabetic patients with dyslipidemia: a secondary analysis of the ACCORDION study

BACKGROUND

The Action to Control Cardiovascular Risk in Diabetes (ACCORD)-Lipid study found no evidence of a beneficial effect of statin-fibrate combined treatment, compared to statins alone, on cardiovascular outcomes and mortality in type 2 diabetes mellitus after 5 years of active treatment. However, a beneficial reduction in major CVD events was shown in a pre-specified sub-group of participants with dyslipidemia. The extended follow-up of this trial provides the opportunity to further investigate possible beneficial effects of fibrates in this group of patients. We aimed to evaluate possible "legacy effects" of fibrate add-on therapy on mortality and major cardiovascular outcomes in patients with dyslipidemia.

METHODS

The ACCORD-lipid study was a randomized controlled trial of 5518 participants assigned to receive simvastatin plus fenofibrate vs simvastatin plus placebo. After randomized treatment allocation had finished at the end of the trial, all surviving participants were invited to attend an extended follow-up study (ACCORDION) to continue prospective collection of clinical outcomes. We undertook a secondary analysis of trial and post-trial data in patients who had dyslipidemia. The primary outcome was all-cause and cardiovascular mortality, and secondary outcomes were nonfatal myocardial infarction, stroke, congestive heart failure and major coronary heart disease. We used an intention-to-treat approach to analysis to make comparisons between the original randomized treatment groups.

RESULTS

853 participants with dyslipidemia had survived at the end of the trial. Most participants continued to use statins, but few used fibrates in either group during the post-trial period. The incidence rates in the fenofibrate group were lower with respect to all-cause mortality, CVD mortality, nonfatal myocardial infarction, congestive heart failure and major coronary heart disease than those in the placebo group over a post-trial follow-up. Allocation to the combined fibrate-statin treatment arm during the trial period had a beneficial legacy effect on all-cause mortality (adjusted HR = 0.65, 95% CI 0.45-0.94; P = 0.02).

CONCLUSIONS

Fibrate treatment during the initial trial period was associated with a legacy benefit of improved survival over a post-trial follow-up. These findings support re-evaluation of fibrates as an add-on strategy to statins in order to reduce cardiovascular risk in diabetic patients with dyslipidemia. Trial registration clinicaltrials.gov, Identifier: NCT00000620.